Radially extended support member for spinal nucleus implants and methods of use

Abstract

A spinal nucleus implant is provided which includes an implant body and an interiorly embedded support member which extends out from the implant body. In one embodiment, the support member is fabric selected from the group consisting of mesh, woven fabric and nonwoven fabric. In one embodiment, the support member includes at least one portion which is located outside of the body, said portion adapted to engage one or more guides for orienting the implant. In one embodiment, the implant is capable of expanding from a compact, substantially dehydrated configuration to an expanded hydrated configuration. A method of manufacturing a spinal nucleus implant is provided which includes coagulating a liquid polymer such that at least a portion of said support member extends beyond the perimeter of the polymer to form a spinal nucleus implant having an interiorly disposed support member which extends out of the polymer. A method of implanting such a spinal nucleus implant is provided.

Description

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a top view of a spinal nucleus implant having an ellipsoid implant body and an interiorly embedded mesh support member spanning the entire body and extending out from opposite ends of the body.

FIG. 2 is a top view of a spinal nucleus implant having an ellipsoid implant body and an interiorly embedded mesh support member partially spanning the entire body and extending out from opposite ends of the body.

FIG. 3 is a top view of a spinal nucleus implant having an ellipsoid implant body and an interiorly embedded mesh support member spanning the entire body and extending out around the entire periphery of the body.

FIG. 4 is a top view of a spinal nucleus implant having an ellipsoid implant body and an interiorly embedded mesh support member partially spanning the entire body and extending out of a portion of the body.

FIG. 5 is a top view of a spinal nucleus implant having an ellipsoid implant body and an interiorly embedded foil support member spanning the entire body and extending out from opposite ends of the body.

FIG. 6 is a top view of a spinal nucleus implant having a kidney-shaped ellipsoid implant body and an interiorly embedded mesh support member spanning the entire body and extending out around the entire periphery of the body.

FIG. 7 is a side view of a spinal nucleus implant having a support member embedded interiorly and extending out beyond the perimeter of the implant body.

FIG. 8 is a side view of a multilayer spinal nucleus implant having five alternating substantially parallel layers, wherein the second and forth layers contain interiorly embedded support members. The support member of second layer extends out beyond the perimeter of the implant body.

FIG. 9 is a top view of a spinal nucleus implant having an ellipsoid implant body, an interiorly embedded mesh support member spanning the entire body and extending out from opposite ends of the body, and two guide members respectively affixed at opposite outwardly extending ends of the support member.

FIG. 10 is a schematic top view of an annulus surrounding a disc space, wherein a dehydrated spinal nucleus implant is shown partially inserted through the annulus into the disc space. A guide member extends from the leading edge of the implant back through the annulus.

FIG. 11 is a schematic top view of the annulus surrounding a disc space from FIG. 10, wherein the dehydrated spinal nucleus implant is shown completely inserted through the annulus into the disc space. The guide member extends from the leading edge of the implant back through the annulus. The schematic depicts the result of a slight pull on the guide member which causes the leading edge of the implant to cant sideways.

FIG. 12 is a schematic top view of the annulus, disc space and implant shown in FIGS. 10 and 11, wherein the guide member has been further pulled to cause the implant to cant transverse to its position when first inserted.

FIG. 13 is a schematic top view of an annulus surrounding a disc space, wherein a dehydrated spinal nucleus implant is shown partially inserted through a first point of entry in the annulus into the disc space. A first guide member extends from the leading edge of the implant through a second point of entry in the annulus. A second guide member is attached to the trailing edge of the implant.

FIG. 14 is a schematic top view of the annulus surrounding the disc space shown in FIG. 13, wherein the dehydrated spinal nucleus implant is shown completely inserted through the annulus into the disc space. The first guide member extends from the leading edge of the implant through the second point of entry in the annulus. The second guide member extends from the trailing edge of the implant back through the first point of entry in the annulus. The schematic depicts the result of a slight pull on the first guide member which causes the leading edge of the implant to cant sideways.

FIG. 15 is a schematic top view of the annulus, disc space and implant shown in FIGS. 13 and 14, wherein the first guide member has been further pulled to cause the implant to cant perpendicular to its position when first inserted. The second guide member is used to stabilize the proximal portion of the implant.

FIG. 16 is a schematic top view of an annulus surrounding a disc space, wherein a dehydrated spinal nucleus implant is shown partially inserted through the annulus into the disc space. A guide member extends from the leading edge of the implant and is contained with the disc space.

FIG. 17A is a schematic top view of the annulus surrounding a disc space from FIG. 16, wherein the dehydrated spinal nucleus implant is shown completely inserted through the annulus into the disc space. The guide member extends from the leading edge of the implant and is contained with the disc space.

FIG. 17B is a schematic top view of the annulus surrounding a disc space from FIG. 16, wherein the dehydrated spinal nucleus implant is still partially inserted through the annulus into the disc space. The guide member extends from the leading edge of the implant through the second point of entry in the annulus.

FIG. 18 is a schematic top view of the annulus surrounding the disc space shown in either FIG. 17A or 17B, wherein the dehydrated spinal nucleus implant is shown completely inserted through the annulus into the disc space. The guide member extends through a second point of entry. The schematic depicts the result of a slight pull on the guide member which causes the leading edge of the implant to cant sideways.

FIG. 19 is a schematic top view of the annulus, disc space and implant shown in FIGS. 16 through 18, wherein the guide member has been further pulled to cause the implant to cant perpendicular to its position when first inserted.

Claims

1. A spinal nucleus implant comprising an implant body and an interiorly embedded support member which extends out from the implant body, said implant adapted and configured to fit within an intervertebral disc space.

2. A spinal nucleus implant according to claim 1, wherein the body has an ellipsoid footprint.

3. A spinal nucleus implant according to claim 1, wherein the interiorly embedded support member is disposed within the implant body in substantially parallel orientation to the footprint.

4. A spinal nucleus implant according to claim 3, wherein the interiorly embedded support member extends beyond the body substantially parallel to the footprint.

5. A spinal nucleus implant according to claim 1, wherein, the support member extends radially beyond and around the entire periphery of the body.

6. A spinal nucleus implant according to claim 1, wherein the support member extends beyond at least one defined portion of the periphery of the body.

7. A spinal nucleus implant according to claim 1, wherein the support member is configured to extend and be folded over a portion of the surface area of the body.

8. A spinal nucleus implant according to claim 7, wherein the support member is configured to extend and be folded over a majority of the surface area if the body.

9. A spinal nucleus implant according to claim 1, wherein the support member is fabric selected from the group consisting of mesh, woven fabric and nonwoven fabric.

10. A spinal nucleus implant according to claim 1, wherein the fabric is made from a material selected from the group consisting of natural polymers, synthetic polymers and metal fibers.

11. A spinal nucleus implant according to claim 1, wherein the support member is a foil made from metal or a polymer.

12. A spinal nucleus implant according to claim 1, wherein the body is made of at least two layers and the support member located between two layers.

13. A spinal nucleus implant according to claim 1, wherein the body is made of alternating substantially parallel layers wherein at least one of the layers contains the support member.

14. A spinal nucleus implant according to claim 1, wherein the support member is at least partially encapsulated by a polymeric coating.

15. A spinal nucleus implant according to claim 1, wherein the support member includes an uncoated portion which is located outside of the body, said portion adapted to engage a guide for orienting the implant.

16. A spinal nucleus implant according to claim 15, wherein the guide is selected from the group consisting of wire, ribbon or string.

17. A spinal nucleus implant according to claim 15, wherein the guide is releasably affixed to the support member.

18. A spinal nucleus implant according to claim 1, wherein the support member is adapted to promote ingrowth of tissue.

19. A spinal nucleus implant according to claim 18, wherein the support member incorporates a medicinal agent which promotes tissue growth.

20. A spinal nucleus implant according to claim 1, wherein the body is made of an elastomeric material.

21. A spinal nucleus implant according to claim 20, wherein the elastomeric material is selected from the group consisting of natural rubber, vulcanized rubber, silicone, polychloroprene, fluropolymers, ethylene propylene diene monomer (EPDM) rubber, polyurethane, polyurea, polystyrene, and polyvinyl chloride.

22. A spinal nucleus implant according to claim 20, wherein the elastomeric material is a hydrogel.

23. A spinal nucleus implant according to claim 22, wherein the hydrogel is selected from the group consisting of polyacrylonitrile, polyvinylalcohol, polyvinylpyrrolidone and derivatives of polyacrylic or polymethacrylic acid.

24. A spinal nucleus implant according to claim 1, wherein the implant is capable of expanding from a compact, substantially dehydrated configuration to an expanded hydrated configuration.

25. A spinal nucleus implant comprising an implant body and an elongate flexible guide member attached to the implant.

26. A spinal nucleus implant according to claim 25 wherein the guide member is selected from the group consisting of wire, ribbon and string.

27. A spinal nucleus implant according to claim 26 wherein the string is a suture.

28. A spinal nucleus implant according to claim 27 wherein the suture is resorbable.

29. A spinal nucleus implant according to claim 25 wherein the guide member is affixed to a support member which is embedded in the interior of the implant body.

30. A spinal nucleus implant according to claim 29 wherein the guide member is releasably affixed to the support member.

31. A spinal nucleus implant according to claim 29 wherein the support member is fabric selected from the group consisting of mesh, woven fabric and nonwoven fabric.

32. A spinal nucleus implant according to claim 29 wherein the support member is a foil made from metal or a polymer.

33. A spinal nucleus implant according to claim 29, wherein the support member is adapted to promote ingrowth of tissue.

34. A spinal nucleus implant according to claim 33, wherein the support member incorporates a medicinal agent which promotes tissue growth.

35. A spinal nucleus implant according to claim 25, wherein the body is made of an elastomeric material.

36. A spinal nucleus implant according to claim 35, wherein the elastomeric material is selected from the group consisting of natural rubber, vulcanized rubber, silicone, polychloroprene, fluropolymers, ethylene propylene diene monomer (EPDM) rubber, polyurethane, polyurea, polystyrene, and polyvinyl chloride.

37. A spinal nucleus implant according to claim 35, wherein the elastomeric material is a hydrogel.

38. A spinal nucleus implant according to claim 37, wherein the hydrogel is selected from the group consisting of polyacrylonitrile, polyvinylalcohol, polyvinylpyrrolidone and derivatives of polyacrylic or polymethacrylic acid.

39. A spinal nucleus implant according to claim 25, wherein the body incorporates layers, wherein certain layers have a different modulus of elasticity compared to other layers.

40. A spinal nucleus implant according to claim 39, wherein the layers are a series of layers which alternate between one having a higher modulus of elasticity and one having a lower modulus of elasticity.

41. A spinal nucleus implant according to claim 40, wherein at least one layer having a higher modulus of elasticity contains the support member at least partially embedded therein.

42. A spinal nucleus implant according to claim 39, wherein at least one of the layers includes a support member having a polymeric coating.

43. A spinal nucleus implant according to claim 25, wherein the implant is capable of expanding from a compact, substantially dehydrated configuration to an expanded hydrated configuration.

44. A spinal nucleus implant according to claim 25, wherein the guide member is at least partially radiopaque.

45. A method of manufacturing a spinal nucleus implant comprising: providing a liquid polymer;providing a mold for containing the polymer;providing a support member;positioning the support member relative to said mold such that liquid polymer can at least partially cover the support member; andcoagulating the liquid polymer such that at least a portion of said support member extends beyond the perimeter of the polymer to form a spinal nucleus implant having an interiorly disposed support member which extends out of the polymer.

46. A method of manufacturing a spinal nucleus implant according to claim 45 wherein the mold includes a first ellipsoid ring portion for receiving liquid polymer and a second ellipsoid ring portion for disposing over the first ellipsoid ring portion and receiving liquid polymer, wherein positioning the support member relative to the mold involves: filling the first ring with said liquid polymer;placing the support member over the first ring such that at least a portion of said support member extends beyond the perimeter of the first ring;positioning the second ring coaxially over the first ring and the support member to produce a substantially liquid-tight arrangement between the first and second rings;filling the second ring with liquid polymer; andcoagulating the liquid polymer to form the spinal nucleus implant having an interiorly disposed support member which extends out of the polymer.

47. A method of manufacturing a spinal nucleus implant according to claim 46 further comprising: providing a first additional ellipsoid ring mold;filling the first additional mold with liquid polymer;placing the implant having an interiorly disposed support member coaxially over the first additional ellipsoid ring mold and in contact with the liquid polymer; andcoagulating the liquid polymer such that the polymer adheres to the implant having an interiorly disposed support member as it coagulates to form a spinal nucleus implant having a first polymeric layer containing the support member and a second polymeric layer, wherein the support member extends beyond the perimeter of the polymeric layers.

48. A method of manufacturing a spinal nucleus implant according to claim 47, wherein the first polymer layer containing the support member has a different modulus of elasticity than the second polymeric layer.

49. A method of manufacturing a spinal nucleus implant according to claim 46 further comprising: providing a second additional ellipsoid ring mold;placing said second additional mold coaxially over the first polymer layer containing the support member;filling the mold with liquid polymer; andcoagulating the liquid polymer such that the polymer adheres to the first polymer layer containing the support member as it coagulates to form a three polymeric layer spinal nucleus implant wherein the support member extends beyond the perimeter of at least one of the polymeric layers.

50. A method of manufacturing a spinal nucleus implant according to claim 49 further comprising: providing a second polymeric layer containing a support member;placing the second polymeric layer containing the support member coaxially over the second ellipsoid ring mold and in contact with the liquid polymer contained by the second ellipsoid ring mold; andcoagulating the liquid polymer such that the polymer adheres to the second polymeric layer containing the support member as it coagulates to form a four polymeric layer spinal nucleus implant.

51. A method of manufacturing a spinal nucleus implant according to claim 50 wherein the support layer extends beyond the perimeter of at least one of the polymeric layers.

52. A method of manufacturing a spinal nucleus implant according to claim 51 further comprising: providing a third additional ellipsoid ring mold;placing said third additional mold coaxially over the second polymeric layer containing the support member;filling the third additional ellipsoid ring mold with liquid polymer; andcoagulating the liquid polymer such that the polymer adheres to the second polymeric layer containing the support member as it coagulates to form a five polymeric layer spinal nucleus implant.

53. A method of manufacturing a spinal nucleus implant according to claim 46 wherein the modulus of elasticity of the coagulated polymer of the polymeric layer having an interiorly disposed support members is greater than the modulus of elasticity of the layer which does not have an interiorly disposed support member.

54. A method of manufacturing a spinal nucleus implant according to claim 45, wherein the polymer is an elastomeric material.

55. A method of manufacturing a spinal nucleus implant according to claim 54, wherein the elastomeric material is selected from the group consisting of natural rubber, vulcanized rubber, silicone, polychloroprene, fluropolymers, ethylene propylene diene monomer (EPDM) rubber, polyurethane, polyurea, polystyrene, and polyvinyl chloride.

56. A method of manufacturing a spinal nucleus implant according to claim 54 wherein the elastomeric material is a hydrogel.

57. A method of manufacturing a spinal nucleus implant according to claim 56, wherein the hydrogel is selected from the group consisting of polyacrylonitrile, polyvinylalcohol, polyvinylpyrrolidone and derivatives of polyacrylic or polymethacrylic acid.

58. A method of manufacturing a spinal nucleus implant according to claim 45, wherein the support member is a fabric selected from the group consisting of woven fabric, nonwoven fabric and mesh.

59. A method of manufacturing a spinal nucleus implant according to claim 45, wherein the support member is a foil made from metal or a polymer.

60. A method of implanting a spinal nucleus implant comprising: providing a spinal nucleus implant having a proximal portion and a distal portion, the distal portion having an elongated flexible guide member affixed thereto, the guide member having a proximal end and a distal end, the proximal end being affixed to the distal portion of the implant;providing a point of entry to the disc space between two vertebrae;inserting the implant into the disc space using the distal portion of the implant as the leading portion of the implant through the point of entry; andmanipulating the guide member to cause the implant to change position.

61. A method of implanting a spinal nucleus implant according to claim 60 wherein said change in position involves canting in arcuate fashion.

62. A method of implanting a spinal nucleus implant according to claim 61 wherein canting in arcuate fashion encompasses an arc ranging from approximately ˜45° to ˜100° relative to the proximal portion.

63. A method of implanting a spinal nucleus implant according to claim 60 wherein the guide member is selected from the group consisting of string, wire and ribbon.

64. A method of implanting a spinal nucleus implant according to claim 63 wherein the string is a suture.

65. A method of implanting a spinal nucleus implant according to claim 64 wherein the suture is resorbable.

66. A method of implanting a spinal nucleus implant according to claim 60 wherein the guide member is affixed to an interiorly embedded support member which extends out from the implant body, the guide member being affixed to a portion of the support member which extends out from the implant body.

67. A method of implanting a spinal nucleus implant according to claim 62 wherein the distal end of the guide remains outside the point of entry and manipulating the guide includes pulling on the guide member to pull the distal portion of the implant along the arc.

68. A method of implanting a spinal nucleus implant according to claim 60 further comprising: providing a second point of entry into the disc space, using a grasping instrument to grasp the guide member from within the disc space, and using the grasping instrument to pull on the guide member and cause the implant to change position.

69. A method of implanting a spinal nucleus implant according to claim 68 wherein the grasping instrument is selected from the group consisting of forceps, hemostat and hook.

70. A method of implanting a spinal nucleus implant according to claim 68 wherein the proximal portion of the spinal implant has a second guide member attached thereto.

71. A method of implanting a spinal nucleus implant according to claim 70 further comprising using the second guide member to manipulate the position of the spinal nucleus implant.

72. A method of implanting a spinal nucleus implant comprising inserting, through an entry point of an annulus, a spinal nucleus implant comprising an implant body and an interiorly embedded support member which extends out from the implant body, said implant adapted and configured to fit within an intervertebral disc space.

73. A method of implanting a spinal nucleus implant according to claim 72 wherein the support member extends beyond at least one defined portion of the periphery of the body.

74. A method of implanting a spinal nucleus implant according to claim 73 further comprising positioning the support member against the annulus to cover the entry point and fastening the support member to the annulus.

75. A method of implanting a spinal nucleus implant according to claim 74 wherein the fastening is accomplished using a fastener selected from the group consisting of suture, staple, screw and clip.

76. A method of implanting a spinal nucleus implant according to claim 75 wherein the fastener is a suture which is attached to the support member.

77. A method of implanting a spinal nucleus implant according to claim 73 wherein the support member has a suture attached to it.

78. A method of implanting a spinal nucleus implant according to claim 77 wherein the suture is used to guide the implant into the intervetebral disc space.

79. A method of implanting a spinal nucleus implant according to claim 77 further comprising suturing and closing the entry point with the suture after implantation of the implant.

80. A method of implanting a spinal nucleus implant according to claim 73 further comprising fastening the support member to vertebral bone.

81. A method of implanting a spinal nucleus implant according to claim 80 wherein fastening is accomplished using a fastener selected from the group consisting of screw, staple, and barb.

82. A method of implanting a spinal nucleus implant according to claim 80 wherein the vertebral bone is a vertebral end plate.

83. A method of implanting a spinal nucleus implant according to claim 73 wherein the support member includes a reinforced area for contacting a fastener.